तीर्थवंशोपदेशः
Tīrtha-vaṃśa Upadeśa: Instruction on the Fruits of Sacred Waters
भरतश्रेष्ठ! जो ब्राह्मण श्राद्धकी समाप्ति होनेपर “अस्तु स्वधा” आदि तत्कालोचित वचनोंका प्रयोग नहीं करता है, उसे गायकी झूठी शपथ खानेका पाप लगता है ।।
bhīṣma uvāca | bharataśreṣṭha! yo brāhmaṇaḥ śrāddhasya samāptau “astu svadhā” ity-ādi tatkālaucitāni vacanāni na prayuṅkte, tasya gāvaḥ kṛtvā mṛṣāśapathasya pāpaṃ bhavati || yudhiṣṭhira! yasmin dine supātra-brāhmaṇaḥ prāpyate, dadhi ghṛtaṃ ca prāpyate, amāvāsyā-tithiḥ ca, araṇyajāni kandamūlaphalapīṭhāni ca labhyante, sa eva śrāddhasyottamaḥ kālaḥ ||
ພີສະມະກ່າວວ່າ: «ໂອ ຜູ້ປະເສີດໃນວົງພາຣະຕະ! ຖ້າພຣາຫມັນໃນຕອນຈົບພິທີ ສຣາດທະ (śrāddha) ບໍ່ເວົ້າຖ້ອຍຄຳປິດພິທີຕາມກາລະ ເຊັ່ນ ‘astu svadhā’ ໃນທັນທີ, ເຂົາຈະໄດ້ບາບເທົ່າກັບການສາບານມຸສາເລື່ອງງົວ. ໂອ ຢຸທິສຖິຣະ! ວັນໃດກໍຕາມທີ່ໄດ້ພົບພຣາຫມັນຜູ້ຄວນຮັບທານ, ມີນົມສົ້ມ (curd) ແລະ ນ້ຳມັນເນີຍ (ghee), ພ້ອມທັງວັນດວງຈັນດັບ (new-moon) ແລະຂອງປ່າເຊັ່ນ ຫົວ, ຮາກ, ແລະເນື້ອຜົນໄມ້—ວັນນັ້ນແຫຼະແມ່ນເວລາອັນດີທີ່ສຸດສຳລັບສຣາດທະ; ເມື່ອເຄື່ອງປະກອບເຫຼົ່ານີ້ພ້ອມກັນ, ໂອກາດນັ້ນເອງກາຍເປັນເວລາມົງຄຸນ.»
भीष्म उवाच
Ritual dharma depends not only on intention but also on correct, timely speech and procedure: omitting the proper concluding formulae of śrāddha is treated as a serious ethical fault. Further, the ‘best time’ for śrāddha is pragmatically defined as the convergence of a worthy recipient and suitable offerings (including amāvāsyā and appropriate foods), emphasizing fitness and availability over rigid calendrical formalism.
In the Anuśāsana Parva’s instruction section, Bhīṣma continues advising Yudhiṣṭhira on dharma after the war. Here he gives specific guidance on śrāddha: the necessity of uttering the concluding words like “astu svadhā,” and the criteria by which a day becomes an excellent occasion for performing the rite.